#app{
    height: 100px;
}
ul{
    margin: auto;
}
li{
    list-style: none;
    float: left;
    width: 120px;
    display: block;
    margin-right: 20px;
}
.clearfix:before
.clearfix::after{
    content: "";
    display: table;
    clear: both;
}
a{
    color: #000;
    text-decoration: none;
}
a:hover{
    color: red;
}
.one li:nth-child(12) a,.one li:nth-child(25) a{
    color: orange;
}